| 摘要 |
PURPOSE:To obtain a dustproof body high in light transmittance and not causing photodecomposition even when it is irradiated with short wavelength light for a long time by precipitating silicon dioxide on a base plate immersed in an aqueous solution of hexafluorosilic acid saturated with silica and separating the obtained thin film and fixing it to a holding frame. CONSTITUTION:The silicon dioxide thin film is deposited and formed on the surface of the base plate, such as a plastic plate, precoated with an aqueous solution of a surfactant and dried by immersing the base into an aqueous solution of hexafluorosilicic acid saturated with the silica, and this film is peeled from the base and fixed to the holding frame 2. Said solution is prepared by dissolving silicon dioxide, such as silica gel or silica glass, in a solution of hexafluorosilicic acid, thus permitting the obtained dust removing body 1 high in light transmittance to prevent opacification of the film 3 due to photodecomposition caused by long time exposure to short wavelength light and deterioration of mechanical strength of the film 3. |
